1. Field of the Invention
The present invention relates to service of connecting a wireless user terminal to a service vendor on the Internet by using a wireless LAN (Local Area Network).
The present application claims priority of Japanese Patent Application No. 2003-159197 filed on Jun. 4, 2003, which is hereby incorporated by reference.
2. Description of the Related Art
In recent years, service of connecting a wireless user terminal to a service vendor on the Internet by using a wireless LAN is increasing (such service as “Hot Spot” is described in non-references that are found on the Internet.
A method (hereinafter, referred to as “network service connecting method”) to achieve such the service includes a first step in which a wireless user terminal searches for an access point and a second step in which the wireless user terminal establishes association through the searched access point with a service vendor.
The first step is performed through a wireless LAN (IEEE802.11). The wireless user terminal, in order to establish association with an access point, acquires, by some methods, an SSID (Service Set Identification) set at the access point. Two methods for a wireless user terminal to establish association with an access point are available.
One method is that a wireless user terminal acquires an SSID which is issued periodically by an access point in its communicable area and, by using the acquired SSID, the wireless user terminal establishes association with the access point, which is referred to as a “Passive Scan” method.
Another method is that a wireless user terminal determines, in advance, an SSID of an access point that the wireless user terminal wants to establish association with and makes inquiries of whether the access point having this SSID exists in an area with which the wireless user terminal is communicable, which is referred to as an “Active Scan” method.
In a second step, an authentication server installed in a service vendor performs authentication of a wireless user terminal. The authentication server judges whether permission is given for connection according to a user ID (Identification) or a password that a wireless user terminal holds.
However, keys (SSID, user ID, and password) to be used in these two steps are different from one another. Therefore, there is a possibility that, even if a wireless user terminal can establish association with an access point in step 1, the user terminal fails in connecting to a service vendor. For example, even if a wireless user terminal succeeds in searching for an SSID of an access point using the Passive Scan method and, by using the SSID as a key, can establish association with the access point, when the wireless user terminal does not have a user ID and a password that the access point provides connection to a service vendor, the wireless user terminal cannot be connected to the service vendor in the end. In such the case, the wireless user terminal has to establish association with another access point that provides connection to the service vendor.
In order to eliminate such useless association processing and to save a wireless resource, a method is available in which keys being used in steps 1 and 2 are associated with one another and the resulting association data is stored; however, if such the method is employed, costs for management of a wireless user terminal increase.